You may be trying to access this site from a secured browser on the server. Please enable scripts and reload this page.

Enter your Email address:

Wolters Kluwer Health may email you for journal alerts and information, but is committed
to maintaining your privacy and will not share your personal information without
your express consent. For more information, please refer to our Privacy Policy.

L-Citrulline Reduces Time to Exhaustion and Insulin Response to a Graded Exercise Test

Abstract

Purpose: Oral L-arginine supplementation has been shown to improve treadmill time to exhaustion and resting insulin sensitivity in individuals with peripheral vascular disease and type 2 diabetes, respectively. Furthermore, L-citrulline supplementation increases plasma L-arginine concentration to a level higher than that achieved by oral L-arginine supplementation. The purpose of this investigation was therefore to determine whether time to exhaustion during a graded treadmill test, as well as plasma insulin and glucose profiles, could be improved with oral L-citrulline supplementation in healthy individuals.

Results: Steady-state submaximal respiratory exchange ratio and V̇O2max were not significantly different between placebo and citrulline trials. Treadmill time to exhaustion was lower following citrulline ingestion than during placebo trials (888.2 ± 17.7 vs 895.4 ± 17.9 s; P < 0.05; N = 17), which was accompanied by a higher rating of perceived exertion during exercise in the L-citrulline compared with the placebo condition. There was also an increase in plasma insulin in response to this high-intensity exercise in the placebo, but not in the L-citrulline, condition (P < 0.05).

Conclusions: It can be concluded that, contrary to the hypothesized improvement in treadmill time following L-citrulline ingestion, there is a reduction in treadmill time following L-citrulline ingestion over the 24 h prior to testing. The normal response of increased plasma insulin following high-intensity exercise is also not present in the L-citrulline condition, indicating that L-citrulline ingestion may reduce nitric oxide-mediated pancreatic insulin secretion or increased insulin clearance.

Enter and submit the email address you registered with. An email with instructions to reset your password will be sent to that address.

Email:

Password Sent

Link to reset your password has been sent to specified email address.

Remember me

What does "Remember me" mean?
By checking this box, you'll stay logged in until you logout. You'll get easier access to your articles, collections,
media, and all your other content, even if you close your browser or shut down your
computer.

To protect your most sensitive data and activities (like changing your password),
we'll ask you to re-enter your password when you access these services.

What if I'm on a computer that I share with others?
If you're using a public computer or you share this computer with others, we recommend
that you uncheck the "Remember me" box.